Health Library

Checking for Ketones

When your cells can’t get glucose (a kind of sugar) to burn for energy, they burn fat instead. This leaves behind acids called ketones in your blood and urine. A buildup of ketones can cause a dangerous condition called ketoacidosis. Your health care team may ask you to check for ketones, especially if you have type 1 diabetes.

When to check for ketones

Ketones in your blood or urine mean that you don’t have enough insulin in your body. You may need to check for ketones when:

Your blood sugar is above 250 mg/dL (milligrams per deciliter).

You are ill or under stress.

You have diarrhea (loose stools), stomach pain, or are vomiting.

You are very thirsty or need to urinate often.

How to check for ketones

You can check for ketones in your urine by using test strips. Your health care team can show you how. Be sure to follow the directions on the package.

Some blood glucose meters can check for ketones in your blood. Talk to your health care team to learn more.